This application claims the priority of German application 198 49 233.2, filed in Germany on Oct. 26, 1998, the disclosure of which is expressly incorporated by reference herein.
Certain preferred embodiments of the present invention relate to a process for exchanging the bearings of a traversing fiber guiding rod made of carbon fibers or the like in a textile machine producing x-packages (crosswound bobbins), in which machine the distance between two adjacent bearings corresponds to at least twice the traversing stroke.
Traversing yarn guiding rods are accelerated alternately by a traversing drive. In particular when the yarn guide rod has a high mass, for example when it is made of steel, the traversing gear is loaded with a high inertia force. In particular in the case of long textile machines, there are furthermore considerable delays in the return motion of direction. It has already been suggested, for example, in U.S. Pat. No. 5,447,795 that the yarn guiding rod be made of carbon fibers in order to reduce the inertia force. As carbon fiber yarn guiding rods are very inflexible, it is known from machines in practice that the bearing points for the yarn guiding rods are no longer, as was previously the case with steel yarn guiding rods, supported adjacent to each winding head, but rather the distance between the bearing points is increased.
Unfortunately, it has been shown that irregular wear occurs repeatedly in the case of the carbon fiber yarn guiding rods. This is disadvantageous as carbon fiber yarn guiding rods are very expensive. When wear occurs in the yarn guiding rods, replacing the bearings with replacement bearings is of no use, as replacement bearings continue to act with the worn areas of the yarn guiding rods.
It is an object of the present invention to significantly increase the life expectancy of the yarn guiding rods despite the occurring wear of traversing fiber carbon yarn guiding rods.
This object has been achieved in accordance with the present invention in that the bearings are collectively exchanged and replaced by replacement bearings, and that the replacement bearings are applied to new bearing points staggered in such a way to the old bearing points that the new bearing points are at a distance to the now exposed old bearing points, which distance corresponds to at least one traversing stroke.
The present invention is based on the knowledge that when the distance between two adjacent bearings corresponds to at least twice the traversing stroke, a maximum of half a length of the yarn guiding rod can be worn. The replacement bearings are then assembled at a new place at which the yarn guiding rod is not yet worn. For example, the bearings can be exchanged for new replacement bearings in yearly rotation. Such replacement bearings are, for example when they are designed as a plastic sliding bearing, decidedly cost-effective. The replacement bearings are then assembled, staggered, at a chosen distance, which must at least correspond to the traversing stroke. Prepared fixing surfaces can be provided on the textile machine for this purpose. As a result of this staggering, the newly applied replacement bearing acts with a nonworn part of the yarn guiding rod. This mating of material is thus ideal. The previous bearing point now remains free of all bearings. When the next change is due, the bearings move a further length along the rod, which length corresponds to at least one traversing stroke, for example the length of one winding station spacing. This process can be continued until the yarn guiding rod is worn practically all along its length and must be subsequently replaced. As a rule, this process can be applied three times.
Due to the process for exchanging the bearings according to the present invention, the exchange of a traversing yarn guiding rod or of individual parts for new ones is considerably delayed.
For example, instead of having to change the yarn guiding rod every year, it can remain for double this time or even three times as long in the textile machine. The new replacement bearings are always applied there, where the yarn guiding rod shows no signs of wear.
In the case of a textile machine producing X-packages, in particular an open-end spinning machine comprising a traversing yarn guiding rod made of carbon fibers, it is purposeful when the bearing points for the replacement bearings to be installed are predetermined. Usually, adjacent to many winding stations or spinning stations, it is possible to affix the necessary sliding bearings or bearing rollers. The affixing points are prepared, even when, for example, only every third bearing point is needed for a bearing. The open-end spinning machine is therefore so designed that the replacement bearings can be installed at any chosen bearing points.
In a further embodiment of the present invention, the bearings are designed as sliding bearings open on one lateral side. Sliding bearings have proven themselves in the case of traversing yarn guiding rods, as in their case no rotating bearing part needs to be additionally accelerated. If the sliding bearings are designed having one lateral side open, a change is quickly and easily carried out without threading. The sliding bearings can be so designed that they vary in their supporting surfaces. For example, one sliding bearing supports only from below and laterally, the other from above, the next one guides from the left side, the one after that from the right side and so on.
The process according to the present invention can be applied advantageously when used textile machines, which have previously operated with yarn guiding rods made of steel and which have short distances between bearings, are modernized by means of re-equipping them with new parts. Firstly, in the case of such a modernization, a larger distance between the bearing points can be provided, and at the same time a carbon fiber yarn guiding rod can be applied, so that subsequently the changing of bearings can be carried out as described above. In a case like this, the process according to the present invention is particularly simple, asxe2x80x94due to the previous short distances between the bearing pointsxe2x80x94affixing points are already present adjacent to each winding point.
With this arrangement where the bearings are open on one lateral side, new bearings can be attached to the same locations, coupled with rotating the traversing rod by 180xc2x0 around its longitudinal axis. Since the traversing yarn guiding rod is not rotatable during its axially driving movements, it would have to be detached from its driving connection and then reconnected again after the 180xc2x0 rotation. This process of rotating the traversing rod could also be carried out without replacement of the bearings, in situations where the wear is primarily at the surface of the yarn guiding rod and not at the bearings.
Another process for replacing the bearings which are open at one lateral side involves attachment of the bearings at the same bearing locations, but with the opening of the bearing, facing in an opposite direction with respect to the bearing being replaced.
These methods according the previous two paragraphs do not require axially repositioning the bearings. However, subsequent to these processes, the other processes of moving the bearings axially to new replacement bearing positions can also be utilized, yet further lengthening the useful life of the yarn guiding rods.
These and further objects, features and advantages of the present invention will become more readily apparent from the following detailed-description thereof when taken in conjunction with the accompanying drawings.